1. Field of the Invention
The present invention relates to an apparatus and method for authentication having means to prevent against wrongful authenticating process, and to a method for registering a person to an authenticating apparatus or appliance using such an authenticating method.
2. Description of the Related Art
There is generally, as a scheme for use in the door lock of an automobile, a widespread of a door lock scheme called, what is called, a smart entry scheme, wherein a user carries a portable unit in a key-folder form to cause unlocking according to an identification signal issued from the portable unit when the user comes nearby the automobile.
FIG. 1 is a diagram explaining a lock system of a conventional smart entry scheme. An automobile 1 has a control section 11 which is, what is called, a microcomputer configured with a CPU (Central Processing Unit), a RAM (Random Access Memory) and a ROM (Read Only Memory). The CPU expands the program stored in the ROM onto the RAM and executes it to control the overall operation of the automobile 1. Note that FIG. 1 shows only a configuration for mainly controlling the automobile 1, omitting the showing, for example, of a drive system and the like.
A lock system 12, under control of the control section 11, manages to unlock and lock the door lock of the automobile. A passive entry authenticating section 13 transmits an inquiry signal to a portable unit 2 through a communicating section 15, and compares between the corresponding identification signal 33a from the portable unit 2 and the identification signal 14a previously stored in a storage section 14 to output a comparison result to the control section 11.
The control section 31 of the portable unit 2 is, what is called, a microcomputer configured with a CPU, a ROM and a RAM, so that the CPU expands the program stored in the ROM onto the RAM and executes it thereby controlling the overall operation of the portable unit 2. The control section 31 controls the communicating section 32 to transmit an identification signal 33a previously stored in a memory 33 correspondingly to an inquiry signal sent from the automobile 1.
Next, explanation will be made on the operation of the smart entry system of FIG. 1.
The control section 11 controls the communicating section 15 to detect the portable unit 2 when approaching to within a distance, and controls the passive entry authenticating section 13 to transmit an inquiry signal through the communicating section 15 to the portable unit 2. The control section 31 of the portable unit 2, receiving the inquiry signal from the automobile 1 through a communicating section 32, reads out an identification signal 33a previously stored in the memory 33 and transmits it to the automobile 1 by controlling the communicating section 32.
The control section 11 of the automobile 1, when recognizing a reception of the identification signal 33a through the communicating section 15, causes it to output the same to the passive entry authenticating section 13. The passive entry authenticating section 13 compares between the identification signal 33a transmitted from the portable unit 12 and the identification signal 14a previously stored in the storage section 14, to output a comparison result to the control section 11. For example, in the case of an agreement in the comparison result, the user carrying the portable unit 12 is considered as an authorized user of the automobile 1. Thus, the lock system 12 is controlled for unlocking. Meanwhile, in the case of a disagreement in the comparison result, the user carrying the portable unit 12 is considered as not an authorized user of the automobile 1 so that the locked state is maintained without operating the lock system 12.
Thus, according to the smart entry system, the authorized user carrying the portable unit 12, if near to within a constant distance of the automobile 1, is allowed to unlock without being conscious of an unlocking operation of the door lock. The locked state can be maintained against an unauthorized user.
In the smart entry system, however, there is a fear of unlocking by an unauthorized user who is not the owner of the automobile 1 by stealing an inquiry signal and identification signal of the automobile 1 and portable unit 2 according a method called relay team attack.
Relay team attack is carried out by two unauthorized users A, B in combination respectively carrying repeaters 51, 52, wherein one of them approaches the automobile 1 while the other is nearby an authorized user as shown in FIG. 2. The repeaters 51, 52 respectively have communicating sections 72, 82 to be controlled by control sections 71, 81, to wrongfully transmit and receive inquiry and identification signals when operating sections 73, 83 are operated.
Namely, the unauthorized user A carrying the repeater 51 goes near (to a close distance to) the automobile 1 whereby the passive entry authenticating section 13 of the automobile 1 transmits an inquiry signal through the communicating section 15. The repeater 51 relays the inquiry signal to transmit it to the repeater 52 carried by the unauthorized user B who is nearby (in a close distance to) the authorized user distant (distant by nearly a middle or long distance greater than a distance at which the usual automobile 1 can detect the portable unit 2) from the automobile 1.
The repeater 52 relays the inquiry signal transmitted from the repeater 51 to transmit it onto the portable unit 2. Thereupon, the portable unit 2 transmits an identification signal 33a as if approaching the automobile 1. The repeater 52 relays the identification signal 33a and transmits it to the repeater 51. The repeater 51 repeats the identification signal 33a transmitted from the repeater 52 to send it onto the automobile 1.
The passive entry authenticating section 13 of the automobile 1 compares between the identification signal 33a relayed from the repeater 51 and the identification signal 14a previously stored in the storage section 14, to output a comparison result to the control section 11. At this time, because the identification signal 33a is the one transmitted from the portable unit 2 possessed by the authorized user, the comparison result results in agreement.
Consequently, despite the one who is approaching the automobile 1 is the unauthorized user A while the authorized user is distant from the automobile 1, the control section 11 controls the lock system to unlock the lock of the automobile 1.
As a result, the unauthorized users A, B can unlock the lock of the automobile 1 without the authorized user being aware, by respectively carrying the repeater 51, 52 to approach the automobile 1 and authorized user.
In this manner, there has been a problem that a wrongful authentication process is carried out by the relay team attack method to illegitimately unlock the door lock of an automobile.
The present invention has been made in view of such a circumstance, which makes it possible to prevent against the wrongful use of a smart entry system.